Researchers utilize engineering to combat world hunger

Biomedical engineering doctoral student Mary Beth Wilson is working on how to make amaranth, a prevalent weed in developing countries, edible. (credit: Alan Vangpat/Senior Photographer)

World hunger and malnutrition: issues that many want to solve, but have yet to do so. However, Philip LeDuc, a professor in mechanical engineering, and Mary Beth Wilson, a Ph.D. student in biomedical engineering, are applying engineering to food in a way that could create a long-term, sustainable solution to malnutrition in Africa.

LeDuc claims that the best ideas come “when you just open your mind sometimes.” That’s what happened in his case: When a ketchup company contacted LeDuc for his expertise in mechanics, he decided to see where it would go, despite laughing at the idea that mechanical engineering had anything to do with ketchup. He soon realized that the way tomatoes are mashed and how they are transported through pipes for packaging affect the taste of ketchup.

“It’s like how my mother used to make mashed potatoes by mashing them herself — it was delicious,” LeDuc said. “Then she bought a blender and used the same exact ingredients as before ... but when she pressed 10 and puréed them, it turned into this soupy mess that my brothers and I refused to eat.”

Everybody loves good ketchup, but LeDuc thought the concept of using mechanical engineering to make food more palatable could be used in a more meaningful way. That’s when he turned to Wilson, his graduate student, whom he remembered had a penchant for cooking.

“I started looking into molecular gastronomy,” Wilson said. “What if you could use scraps of food, like peels, and turn it into something good?”
A few months later, LeDuc received an email from the Bill and Melinda Gates Foundation about its Grand Challenge Exploration Grant, a $1 million award for a research idea that explores nutrition for infants and children.

“What if you could take a nutrient-rich plant that already existed inside a third-world country, but people just wouldn't eat it?” LeDuc explained. “And what if you could use mechanics to change that taste, to make it from something they don’t like to something they do like?”

Wilson did some research and found that there is a weed called amaranth that is high in vitamin A and other nutrients, but is not eaten because of its bitter taste.

“What made amaranth attractive was the widespread nature of its growth and the fact that there are many varieties throughout the world,” Wilson said. “Also, since it is a weed, it can pretty much be grown anywhere, so we figured it could be grown in Pittsburgh.”

In a mere 10 days, LeDuc and Wilson went from being intrigued by the concept of how mechanics could affect food palatability to writing a proposal for the Grand Challenge Exploration Grant. His project would use mechanical engineering to study how different methods of preparing amaranth could change its taste, as well as increase its nutritional value by altering the plant's cellular structure to optimize the release of its nutrients during digestion.

Several months later, their hard work and creative thinking paid off: They received the grant.

For the past year, LeDuc and Wilson have been exploring the effects that different ways of preparing amaranth will have on its nutritional value. For example, chopped carrots retain most of their vitamins while steamed carrots lose their water-soluble vitamins.

“We are taking the plant and we’re cutting it up in different ways and at different speeds,” LeDuc said. “For example, how does making it very fine versus chopping it into bigger chunks change the nutritional value?”

Along the way, they have had help from the Phipps Conservatory, where the amaranth is grown. And, as it turns out, the president of the Amaranth Institute, which is devoted to studying how the plant can be better utilized, is a Carnegie Mellon alumnus who has been eager to help out the researchers.

“It’s in its early stage, but it has high end potential,” LeDuc said. The project explores a new field of science and tackles a tremendous goal: ending world hunger. “But that’s what we’re about at Carnegie Mellon,” LeDuc said. “High risk and high rewards.”